Enantioselective Hydroxylation of Dihydrosilanes to Si-Chiral Silanols Catalyzed by In Situ Generated Copper(II) Species

Angew Chem Int Ed Engl. 2022 Aug 8;61(32):e202205743. doi: 10.1002/anie.202205743. Epub 2022 Jun 24.

Abstract

Catalytic enantioselective hydroxylation of prochiral dihydrosilanes with water is expected to be a highly efficient way to access Si-chiral silanols, yet has remained unknown up to date. Herein, we describe a strategy for realizing this reaction: using an alkyl bromide as a single-electron transfer (SET) oxidant for invoking CuII species and chiral multidentate anionic N,N,P-ligands for effective enantiocontrol. The reaction readily provides a broad range of Si-chiral silanols with high enantioselectivity and excellent functional group compatibility. In addition, we manifest the synthetic potential by establishing two synthetic schemes for transforming the obtained products into Si-chiral compounds with high structural diversity. Our preliminary mechanistic studies support a mechanism involving SET for recruiting chiral CuII species as the active catalyst and its subsequent σ-metathesis with dihydrosilanes.

Keywords: Asymmetric Catalysis; Copper; Metathesis; Silanols; Single-Electron Transfer (SET) Oxidation.